Screw-cutting machine.



No. 675,834. Patented June 4, I90I. D. LAKE.

SCREW CUTTING MACHINE.

6 Sheets-Shoot I.

(Application ledAug. 24, 1900.)

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(llo Model.)

No. 675,834. Patented lune 4, l90l'. D. LAKE. scnEw crrma uAcHmE;

(Lpphcationbd Aug 24 1900) 6 Sheets-Sheet 2.

(lo Model.)

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SCREW CUTTING MACHINE..

(Applicivn Mad A 94, 1900.) (No Model.) s 6 Sheets-Sheet 3.

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No. 675,834. Patented lune 4, |901. D. LAKE.

SCREW CUTTING MACHINE.

(Application led Aug. 24, 1900.)

6 Sheets-Shack 4.

(N0 Model.)

1 l i I l l l No. 675,834. Patented lune 4, I90I. D. LAKE.

SCREW CUTTING MACHINE.

- (Application Bled Aug. 24, 1900.) (lo Model.) 6 Sheets-Sheet 5.

me cams anzu cn, moraunm.. wnnwovon. u. c

(No Model.)

Patented lune 4, |90I. D. LAKE.

SCREW CUTTING MACHINE.

(Applicntion led Aug. 24, 1900.)

6 Sheets-Sheet 6.

UNITED STATES PATENT OEEICE.

DAVID LAKE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF THREE- FOURTHS TOEDWIN IV. CRELLIN, OF SAME CPLACE, AND JOIIN LEISEN- RING, OF UPPERLEIIIGII, PENNSYLVANIA.

SCREW-CUTTING MACHINE.

SPECIFICATION forming part of Letters Patent No. 675,834, dated June 4,1901.

Application tiled August 24, 1900. Serial No. 27,898. (No model.)

T0 all whom it may concern:

Be it known that I, DAVID LAKE, a citizen of the United States, residingin Philadelphia, Pennsylvania, have invented certain Improvements inScrew-Cutting Machines, of which the following is a specification.

The object of my invention is to so construct a machine for cuttingscrew-threads that the'thread can be cut on a bar of any length and ofany diameter in a continuous operation and the thread can be cut on anypitch desired. This object I attain in the following manner, referencebeing had to the accompanying drawings, in which-- Figurelisasideview ofmyimprovcd screwcutting machine. Fig. i is a plan view. Fig. 3 is a planView of the cutting end of themachine, showing the cutter in the act ofcutting a screw on the bar. Fig. 4L is a longitudinal sectional view onthe line 4 et, Fig. 3. Fig. 5 is a vertical sectional view on the line 55, Fig. et. Fig. 6 is an end view of the machine. Fig. 7 is a section onthe line 7 7, Fig. 4; and Fig. 8 is a section on lthe line 8 8, Fig. (5.

A is a hollow standard mounted on a suitable foundation so that it willbe rigid.

a d are guides for the vertically-adjustable bed-carrying piece B. Thispiece has portions h h, which conform to the guides, and has anextension b', which enters a vertical slot a in the standard, so thatthe piece Il is free to slide vertically on the standard. Oarried by thepiece B is a bed-plate B'. This bed-plate extends rearward and carriesthe rear portion of thc machine. A bracket B2 stiffens the bed, as itwill be understood that the bed must be rigidly supported and capable ofvertical adjustment.

I will rst explain the means for adjusting the hed.

O is a shaft which can be provided with a suitable handle, and on thisshaft is a bevel- Wheel c, gearing with the bevel-wheel c on a verticalshaft C'. The lower end of the vertical shaft Cl is threaded and passesthrough a nut o2 on a bracket a2, projecting from the standard, so thaton turning the shaft C the threaded shaft C will turn in the nut andwill either raise or lower the bed B. The shaft C may be provided with ahand, and on the frame may be placed a dial, as shown in Fig. 5, toindicate the extent of movement.

D is the hollow screw-threaded carrier for the rod on which the threadis to be cut. This threaded carrier has its forward bearing in acarriage D@ having guides d d, traveling on guideways E E, supported oneach side of the machine by brackets E', which are bolted to thebed-plate B. The rear of the screwthreaded carrier travels through a nutfin the rear bearing F, as clearly shown in Figs. l and 2. On the frontof the carriage D is a chuck D2, having jaws d. These jaws are arrangedto grasp the rod on which the thread is to be cut and clamp it securelyto the carriage, so-that it will be fed at a given speed according tothe pitch ot' the thread and the depth of cut desired.

G is the carrier for the cutting-tool and its drivingmechanism.Thiscarrier isconstructed as follows: The carrier has two segmental armsg g, which rest on the upper portion of the standard A, and the arms areslotted at g. Bolts g2 pass through the slots into the standard andsecure the carrier in its adjusted position. I preferably form a rib a3on the standard and groove the under side of the arms g of the carrier.The rib is on a radius taken from the center of the cutting-line of thetool.

I is the cutting-tool shaft, and i is the cutting-tool. This tool in thepresent instance is of the form clearly shown in Fig. 3, having a seriesof cutting-teeth on its periphery. The cutter inthe present instance isso formed as to cut a thread with one side vertical and the other sidebeveled; but it will be understood that any form of thread maybe cut,according to the shape of the cutting-tool, the position of the tool,and the feed of the bar.

The shaft I is mounted in bearings G, as clearly shown in Fig. 4. Thebearings are preferably bushed, and the shaft I has a screw-threadedportion z", on which are nuts 2, so as to take up for any lost motionwhen desired. The cutter t is held to the spindle by a nut t3 in theordinary manner. Keyed to the spindle is a spiral gear-wheel I', andmeshing with this is a Second spiral gear- Wheel h on the driven shaftH, mounted in IOO bearings h on the carrier G. This shaft is driven by abelt which passes over a beltpulley h2 from a belt-pulley h3 on a shaftIl, mounted in bearings in the bracket G2, depending from the carrier G.The shaft is also mounted in bearings H2, swiveled on a vertical shaftH3, having its bearings (t4 on a fixed portion of the standard. Thevertical shaft 113 has a double gear-wheel 7L", or two bevel gear-wheelsmay be placed back to back, if desired. One of the gear-wheels h4 mesheswith the bevel gear-wheel h5 on the shaft II, while the other mesheswith a gearwheel 7L6 on the driving-shaft H, mounted in suitablebearings in the standard. This d riving-shaft has a cone-pulley h7 forchanging the speed of the driving mechanism.

It will be noticed that the vertical shaft Il3 is on a vertical linearound which the carrier Gis adjusted-namely,thelinedrawn through thecenter of the cutter y[-so that no matter what position the carrier G isin the drivingshaft H4 will always be in gear with the shaft H and willdrive the cutter through the shaft II and cutter-spindle I.

In order to steady the work at the cutter, I provide two sets of jaws Jand K. The bearing portions of each set of jaws are V- shaped, so as tohold the work firmly, preventing it from moving out of line, yetallowing it to pass freely through the jaws when fed forward by the feedmechanism. The jaws J are arranged forward of the tool and the jaws Kare arranged back of the tool. The jaws K are only used when it isdesired to cut a thread on a rod up to thel chuck. Then the jaws J aremoved out', so as to clear the chuck, while the jaws K are moved intoposition to guide the rod. Ey this arrangement the major portion of therod on which the thread is cut is not in contact with anybearing-surface, as the jaws J guide the rod just prior to its beingcut, and it is only when the jaws K are in position that the rod isguided by its threaded portion. Each of thejaws is mounted on carriers Jand K, respectively, and these carriers are supported on suitablebearings secured to the bed 13 of the machine. The jaws are moved towardand from the center of the rod to bc cut by ordinary adjusting screws.l2 and K2, respectively. The adjusting-screw J2 has a head to which akey can be applied, while the screw K2 is geared to a spindle if atright angles to the screw, aud this spindle is provided with a head, sothat a key can be applied. This construction is necessary, as theadjustable carrier G for the tool will not allow for the application ofa key to the end of thc shaft K2.

Mounted between the two sets of jaws J aud K is a clearing-tool Il. Thistool enters the groove between thc threads of the screw immediatelyafter the cutter has cut the groove, so as to finish and clean thethread. This cutter is of the peculiar form shown in Fig. 5, beingmounted on acarriage L, moved toward and from the rod being cut by ascrew Z, mounted in a bearing L2, secured to the bedplate B, as shown inFig. 5.

I will now refer again to the mechanism for feeding a rod to the cutter.As before remarked, the hollow screw-rod D is journaled to the carriageD. The construction of the coupling is clearly shown in Fig. 4. Atubular section D3 is mounted in the bearings of the carriage D, and acoupling D4 couples the tubular screw D to the section D3, so that thecarriage D is fed forward as the screw D revolves. The spindle D5 of thechuck D2 is hollow and extends through the tubular section D, as clearlyshown in Fig. 4. The

spindle has a shoulder at one end and is threaded at the opposite endfor the reception ofthe confining-nuts. On the spindle of the chuck iskeyed a gear-wheel d?, which is geared through a gear-wheel (Z3, securedto a sleeve d4, splined to au intermediate wheel with a shaft M. Theshaft )I turns the chuck at the proper speed, and with it the rod to becut, while the screw-spindle D is fed forward, so that by feeding thescrew-spindle D forward and turning the shaft M at a given speed,according to the pitch desired, and setting the cutter at an angle toagree with the pitch a screw-thread will be cut accurately upon the rod.

In order to feed the hollow screw-spindle forward and to drive the shaftM, I use the following gearing, referring to Figs. l, 2, 6, and S: Onthe shaft lI is a worm-wheel n, which gears with a worm n. on a shortshaft N. This shaft is coupled to a shaft N by a gimbal-joint n2, andthe shaft N is coupled by another gimbal-joint n3 to a short shaft N2,having its bearings in the frame F at the end of the machine, as clearlyshown in Fig. G. The shaft N"2 has agcar-wheel j), which meshes with anintermediate wheel p' on a stud p2, mounted in the frame F, and thisintermediate wheel meshes with a gear-wheel 193 on thc hollow spindle D.The wheel p meshes with a gearwheel p", carried by a stud 19"', on whichis a pinion [1, which meshes with a wheel m on the shaft M. The spindlep is carried by a pivotcd arm P, which can be locked in differentpositions by a bolt jfl', which rests in a slot in the arm. This is thesame construction as an ordinary back gear ou a lathe. Ey changing thegears p p p3 the speed of the carriage forward can be regulated, and bychanging the gears p1, p", and m the speed of the shaft M can beregulated. The gear-wheel p3 is held in position by the bearing F and ayoke Q, which is dctachably secured to a bracket on the base, Figs. (iand S. The nutf can be thrown into and out of mesh with the threads ofthe spindle D by a lcverf, asthenutfisahalf-nutaud mounted in guides inthe frame F. On one of the guideways E is a rack S, and mounted on thebear- IOO IIO

ing s on the carriage is a shaft s', having a gear-wheel Q?,which mesheswith the rack, and this wheel is turned by a handle s, so that when itislwished to move the carriage forward or back by hand the lever f isoperated to throw the nutfout of mesh with the screwspindle D. Then thecarriage, with its spindle, can be moved toward or from the cutter byoperating the handle s3; but when it is wished to feed the carriageforward by power the leverf is operated to throw in the nutf in meshwith the screw-spindle I), and the carriage can be fed forward by power.The chuck D2 may be of any ordinary type, so formed that a key can beused to clutch the jaws to the rod.

It will be seen that I simply use a tool to cnt one portion of the rodat a time and turn the rod and feed it to the cutter as the cutterrotates, and with one cut I finish the thread. l do not require two orthree sets of dies or sets of cutters. The finishing-tool which followsthe cutis simply for the purpose of cleaning the thread after thecutter. Furthermore, it will be seen that by having the tubular chuckand screw-spindle D, I can thread a rod of any length, and by having thejaws at the cutter the machine can be made compact and sections of therod can be cut at intervals.

The chuck is operated so as to rmly grasp the rod as it is fed to thecutting-tool, and the jaws J J are so set that the rod will pass betweenthe jaws without vibration, the jaws steadying it against the cuttingaction of the cutting-tool, and if the machine has a hollowscrew-spindle D of such a length that it can feed forward, say, fourfeet of the rod at one operation the chuck need not be released until athread four feet long is eut upon the red. Then all thatis necessaryisto clamp the jaws J J to the rod by turning the adjustingscrews,releasing the chuck and backing it olf by means of the rack and pinion,and then attaching the clutch again to the rod and backing olf the jawsJ J slightly, and the cutter can proceed with the work of cutting thethread at the point where itpreviously stopped.

I have found by experience that the thread is continuous and the marksdo not show where one section of thread stops and another begins.

The machine is able to cut a thread very quicklyand accurately on anylength of rod, and when it is desired to work up to the head-*forinstance, as on a bolt-the jaws J J are backed olf and the jaws K K areset to guide the rod, so as to allow the chuck to come up to thecutting-tool.

l claim as my inventionl. The combination in a screw-threading machine,of a hollow-threaded carrier for the blank upon which a thread is to beeut, means for feeding the carrier laterally, means for turning theblank, a cutter, an adjustable carrier therefor and means for operatingthe cutter, substantially as described.

2. The combination in a screw-cutting machine, of ahollowcarrier for theblank, means for rotating the carrier, means for rotating the blankindependently of the carrier, a cutter, and means for rotating thecutter, substantially as described.

3. The combination in a screw-cutting machine, of a carriage, a hollowfeed-screw for feeding the carriage and through which the blank ispassed, a chuck on the carriage engaging the blank, means for turningthe chuck independently of said hollow feed-screw, and a cutter,substantially as described.

4. The combination in a screw-cutting machine, of a carriage, a hollowfeed-screw for the carriage, a chuck on the carriage, a cutter, drivingmechanism for the cutter, and mechanism for feeding and other mechanismfor turning the blank, substantially as described.

5. The combination in a screw-cutting lnachine, of a standard, a cuttercarried by the standard, means for rotating the cutter, a bed verticallyadjustable on thc standard, and a hollow tubular carrier for the blankto be eut, said carrier being mounted on the bed, substantially asdescribed.

G. The combination in a screw-cutting machine, of a standard, anadjustable carrleron the standard, a cutter carried by the standard, avertically-adjustable bed, guides thereon, a carriage on said guides, ahollow feedscrew for the carriage, a chuck for the blank mounted on thecarriage, and means for rotating the chuck and fo' rotating thefeedscrew, substantially as described.

7. The combination in a screw-machine, of a standard, a bed thereon, acarriage for the blank mounted on said bed, means for feeding thecarriage and for turning the blank, an adjustable carrier for thecutter, a vertical driving-shaft on a line with the cutter, andmechanism between the said shaft and the cutter-shaft, substantially asdescribed.

8. The combination in a screw-cnttingmachine, of a standard, a bedvertically adjustable on the standard, a carriage on the bed, a chuckfor the blank on the carriage, a long hollow feed-screw coupled to thecarriage, a nut on the bed, means for turning the screw and forrevolving the chuck, and a cntteron the standard, substantially asdescribed.

i). The combination in a screw-cutting machine, of a cutter, meansfordriving the same, a bed, a carriage on said bed, a hollow feedscrewfor the carriage, a chuck for engaging the blank, a shaft runningparallel with thc feed-screw, and means for turning the shaft and thefeedscrew, substantially as dcscribed.

l0. The combination in ascrew-cutting machine, of a cutter, drivingmeans therefor, a

IIO

carriage, a, hollow feed-screw connected tol In testimony whereof I havesigned my said Carriage, a chuck journaled in the carllame t0 thisspecification in the presence of lo ringe in line with the feed-screw, adrivingtwo subscribing Witnesses.

shaft for the chuck, a train of gears fordi'iving both the shaft and thefeed-screw, and a DAVID LAKE' shaft coupling the train of gears t0 thecutfitnessesz ter-driving mechanism, substantially :1 -s de- XVILL. A.BARR,

scribed. JOS. IT. KLEXN.

